h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I love riddles, not the mathematical ones, the ones like

'A man is found hung in his room with no other furniture in it. There is a pool of water around his feet, how did he hang himself?'

Anyway that was a relitivly easy one. If anyone knows any good riddles or even stupid ones i would love to hear them. The hardest riddle i ever heard was this one:

'Two men (Let's call them Bill and Ben) go into a restaurant. For old times sake they order albatross soup. Ben takes one taste of the soup, looks up in horror, runs out of the restaurant and kills himself.'

If you want to know the answer to this one you'll have to ask me some questions.